Destructible link device



Oct. 30, 1956` G. 4DE JEAN DESTRUCTIBLE LINK DEVICE Filed MM 1o, 1955 In Veni-or by f Afforneys United States Patent O Y a ff f fznsif DESTRUCTIBLE LINK DEVICE Lucien Guy Dejean, Paris, France, assignor to Societe Nationale de Constructions Aeronautiques du Sud- Ouest, Paris, France a 1 Application May 10, 1955, Serial No. 507,371

Claims priority, application France May 18, 1954 i p p i achim. (c1. 244-138) This invention relates to a device comprising a link for temporarily attaching two bodies together, the said device comprising means to partly destroy said link, so as-to cause automaticdisconnection of said bodies.

One object of the invention is to provide a device of this type which, while being extremely simple and cheap,

Y is nevertheless capable ofensuring a safeV and reliable attachment of the two bodies, as long as the said link destroying means are not operated, as well as a safe disconnection upon operation of the said means.

A more specific object of the invention is to provide a deviceV of the type described, wherein the said partly destructible link is constituted by a tubular braid made of textile or metal fabric and wherein the said link destroying means are constituted by a blasting cartridge which has been introduced into said tubular braid through an enlarged mesh of the fabric without breaking of the threads or wires, means being provided for ring the said cartridge from outside the braid.

There is thus provided an extremely simple destructible link device and the mechanical resistance of the braid is not impaired. p,

Moreover, when the said braid is subjected to a tensional stress, it compresses the cartridge thus increasing the blasting power of the same while the threads or wires to be broken are thus tightly pressed against the'cartridge, which makes their destruction safer.

Still another object of the invention is to ensure remote fpowder .or-explosive, substance may thus befintroducedinto said braid. This powder may be, for instance, blastingpowder'... v ,21 l' l V, v i.,

The casing Z of the cartridge mayjbefvof any material and, preferably, parained cardboard or plastic material, for instance a vinyl compound. In the case where the braid has a small inner diameter and is made of textile threads, said cartridge may be a mere tube Yof thermoplastic material with an inner diameter equal to that of the slow match 4 and having one end thereof threaded over said slow-match while the other vend of said tube is obturated by being crushed` or twisted subsequent to a suitable heating operation. T'he length of the slow-match 4 is proportional to the desired delay of operation (as a rule 1 centimeter per second). The opposite end of the slow-match 4 is furnished with an igniting device 5 which, in a known manner, may be a tube adapted to cover the match and partially filled with a fulminating compound 6 into which is embedded Va barbed wire 7 terminating into a pull ring 8. Upon the barbed wire being tornV up, the fulminating compound is red and lights up the slow match which causes the cartridge to explode after the aforesaid desired delay.

When a metal braid isl used, the cartridge 2 may contain 'a high explosive material and may be provided with a detonator.

When the braid 1 is taut, the threads or wires which it is made of are pressed close to each other and snugly tit against the cartridge thus compressing it.

The explosion of the cartridge, thus, is able more easily to destroy all the wires at once.

' In Fig. 3, the braid 1 forms, by splicing, stitching or knotting, a closed loop engaged, on one hand, into a ring 9 rigid with a load to be parachuted and, on the other hand, into a ring 10 arranged at the foot of the shroud Y lines of an extracting parachute.

firing of the above mentioned cartridge through a slowmatch of conventional type, which permits delaying theV said tiring and hence the desiredidisconnection by any desired time.

The invention finds a particularly interesting application in parachutes provided with an extracting canopy for-delaying the opening of the main canopy by temporarily anchoring Vthe saidextracting canopy on the load.

vOther objects and advantagesrof the invention will Vbe apparent from the following detailed description, togetherV l f withnthe accompanying drawing, submitted for-purposes 3 v of illustration only andlnot intended todene the scope of the invention, reference being had for that purpose i to the subjoinedclaim.A

Onthese drawings: i

, i Fig. 1 is `an elevational `View of a destructible connect-v`A ing means according too-the' invention; A,

Fig. 2 is an interrupted longitudinal section of the pyrol technical portionof the device shown in Fig. l.;'and

.i Fig. 3 shows the application ofthe invention to the de.

layed Opening Offajparachute;` i

The mbuiarbraidV 1 showntin Figlia formed eitherV of metal wirespor threads made' of any suitablenatural orV Vartificial textile material.`

braid. v An explosive cartridge Z (Fig. 2) containing a load The extracting parachute spread wide open as soon as the load 14 is jettisoned does not materially slow down the descent of -said load; it, however, exerts a pulling force upon the loop formed by the braid. At a predetermined moment, this loop is broken by the load of explosive lighted up by the slow match 4, and the extracting parachute then exerts a pulling force upon the string 12 which pulls out and spreads open the main parachutey out of its envelope 13.

VAs a modification and in order to cause the closed loop more safely to release the two bodies it connects together,

it is suicientto provide only one of the two rings 9, 10V secured to one of the bodies, the braid being secured to Y Operation fof the igniting. device 5 may be ensured by Y `hand at theimoment when thev load is jettisoned or, .preferably, b y a pulling action exerted on the igniting device at l the mOmQUf-he loadi-sjettisoned by Va cablerattached to the airplane.'v

While the invention has been described with particular `reference to a preferred embodiment, itis not intended-to` limitthe scope of-theinvention tol the embodiment illus-2 trated, 'nor otherwisethan bythe Aterms fof the subjoined claims. Y Y .l

; What is claimed is: Y i

A` destructible link device for releasably interconnect ing two bodies, comprising, in combination, a'tubular braid adaptedto interconnect said bodies and,V having a` Patented oaso, 1956 lateral opening, an explosive cartridge in said tubular braid, an ignition device for `said cartridge located externally of said braid, and a slow match interconnecting said ignition device and said cartridge through said opening, saidv cartridge comprising a tubular envelopeA member of thermoplastic material having one lend portion tightly connected to the inner end of said slow match and having its other end closed.

Y References Cited in the file of this patent UNITED STATES PATENTS 

